Effects of Yoga Asana Practice Approach on Types of Benefits Experienced.

CONTEXT: Modern science and the classic text on hatha yoga, Hatha Yoga Pradipika, report physical, mental, emotional, spiritual, and relational benefits of yoga practice. While all have specific suggestions for how to practice, little research has been done to ascertain whether specific practice approaches impact the benefits experienced by practitioners. AIMS: Our aim was to relate the experience level of the practitioner, the context of practice approaches (time of day, duration of practice, frequency of practice, etc.), and experience level of the teacher, to the likelihood of reporting particular benefits of yoga.
METHODS: We conducted a cross-sectional descriptive survey of yoga practitioners across levels and styles of practice. Data were compiled from a large voluntary convenience sample (n = 2620) regarding respondents' methods of practice, yoga experience levels, and benefits experienced. Multiple logistic regression was used to identify approaches to yoga practice that positively predicted particular benefits.
RESULTS: Frequency of practice, either with or without a teacher, was a positive predictor of reporting nearly all benefits of yoga, with an increased likelihood of experiencing most benefits when the practitioner did yoga five or more days per week. Other aspects of practice approach, experience level of the practitioner, and the experience level of the teacher, had less effect on the benefits reported.
CONCLUSIONS: Practice frequency of at least 5 days per week will provide practitioners with the greatest amount of benefit across all categories of benefits. Other practice approaches can vary more widely without having a marked impact on most benefits experienced.

Introduction

Participation in yoga practice has grown widely, with over 300 million practitioners worldwide.[1] This growth is likely due to the broad range of benefits attributed to yoga. Modern yoga asana practice primarily encompasses the practices of hatha yoga. The classic Indian text on hatha yoga, Hatha Yoga Pradipika, says that hatha yoga creates a “balance of the interacting activities and processes of the physical body, mind, and energy,” and that, “these practices will at least bring optimal health and tranquility of the mind.”[2]

Modern science supports the Hatha Yoga Pradipika and reports physical, mental, emotional, spiritual, and relational benefits[34567] of yoga practice. Previous research shows that yoga practice improves physical health[489] and encourages the maintenance of other health-positive lifestyle behaviors.[10] Specific physical benefits include improved balance,[611] strength,[6] flexibility,[6] energy level,[4] and sleep;[4912] improved spinal disc health,[13] and positive impact on healing or managing pain and injury in general.[345614] Moreover, yoga has been shown to reduce anxiety[6915] and stress,[691215] as well as improve mindfulness,[616] executive function,[1117] mood,[17] emotional state,[12] self-compassion,[18] happiness,[4] and overall mental health.[8] Relational benefits include increased compassion and generally improved interpersonal relationships.[412] Spiritual impacts of practice include spiritual well-being and a sense of closeness with God.[3]

While modern styles of yoga asana practice have specific suggestions for how to practice, limited research has been done to ascertain whether some aspects of practice approach, such as duration, frequency of practice, or time of day, are more likely to produce particular types of benefits. The Hatha Yoga Pradipika suggests that daily early morning practice of a minimum of 30 min is necessary for benefits to occur.[2] Consistent with this idea, Kishida and Elavsky, in 2017,[18] found that the duration of each yoga session was related to benefits experienced. In addition, several studies have reported that the frequency of weekly yoga practice[41019] or overall yoga expertise[20] are related to benefits reported.

The experience level of the yoga teacher has similarly not been evaluated with respect to its impact on the benefits of yoga. Traditionally in the context of hatha yoga's origin in India, whether one had sufficient experience to teach yoga was judged on an individual basis by one's teacher, after many years of practice.[21] However, as a result of yoga's rapid rise in popularity and the recent increase in teacher training programs, the experience level of yoga teachers varies considerably.[22] There is currently no national or international certifying board that issues licenses for yoga instructors. What exists are voluntary registries of yoga teachers that may issue a “registered yoga teacher” or “certified yoga teacher” designation, and which, in many cases have low barriers to entry.[2223] Among recent surveys of yoga practitioners, only Birdee et al., in 2017,[8] reported on the experience of the yoga teacher and its association with the benefits of yoga. Participants with a certified teacher reported greater global physical health than participants with a noncertified teacher.[8]

The effects of yoga practice on long-term practitioners are largely unknown. Most clinical yoga research to date has evaluated the effects of short-term yoga treatments on beginner practitioners, for example, Yadav et al., 2016[24] and Alexander et al., 2013[9] and as summarized in the review paper from Field, 2011.[6] Recent surveys of yoga practitioners suggest that long-term practitioners may experience different types of benefits than newer practitioners.[1014] However, several studies combine factors such as years of practice with the frequency of practice to create a single measure, making it difficult to ascertain the significance of each factor.[1420]

In summary, the Hatha Yoga Pradipika offers some specific methods for practice including frequency, duration, and time of day.[2] Similarly, modern hatha yoga styles offer suggestions for how to practice, which often mirror the methods described in the Hatha Yoga Pradipika. However, little research has been done to relate these variables to the likelihood of reporting the particular benefits of yoga. Previous research specifically refers to the need to characterize the long-term effects of yoga practice[24] and the variations in yoga practices and their effects on types of health benefits.[8] To address these questions, we surveyed yoga practitioners across levels and styles of practice. We compiled data from a large sample of respondents regarding their methods of practice, as well as yoga experience levels, and related that information to physical, mental, emotional, spiritual, and relational benefits that participants experienced.

Methods

As part of a larger study,[25] we distributed a cross-sectional descriptive survey and collected a voluntary convenience sample. The survey was distributed internationally through social media notices posted by Yoga International and Yoganatomy.com, which detailed the intent of the project and contained a link to the survey. In addition, that information was E-mailed to members of the United States-based yoga teacher registry, Yoga Alliance, and members of Yoganatomy.com. The self-administered questionnaire was available to survey respondents in English between August 23, 2016 and November 7, 2016. In this manuscript, we report solely on self-reported benefits experienced by respondents.

Ethical considerations

On clicking the link to begin the survey, participants indicated their “informed consent” before continuing. Participants could opt out of answering any question. No personally identifying information was collected unless participants indicated their interest in participating in a follow-up study by voluntarily offering their E-mail address. Otherwise, all responses were anonymous, and all information was stored on a secure server.

Survey questions

The survey was designed to summarize both positive and negative experiences of modern hatha yoga participants. Survey questions specifically addressed: (1) demographics, (2) yoga practice habits, and (3) self-reported experiences in yoga practice. This manuscript presents results with respect to the subset of yoga participants who answered any question regarding potential physical, mental, emotional, spiritual, and relational benefits of yoga asana (n = 2620).

Data analysis

Data related to demographics and yoga practice habits of respondents were reported previously[25] [Table 1]. All yoga and benefits data were analyzed across styles of practice, as more than half of respondents (58%), indicated that they practiced multiple styles. Survey participants had the opportunity to mark, in a multiple answer question, any or all of 11 potential benefits of yoga that they might have experienced [Table 2]. The results of this question were then formatted as a series of dichotomous variables for the purpose of analysis.

Table 1

Demographics of survey participants

	Percent of sample	Sample size (n)
Age		2630
15-30	10
31-45	44
46-60	35
61+	11
Gender		2625
Female	84
Male	15
Other/prefer not to say	<1
Continent/area of residence		2494
North America	48
South America	2
Europe	38
Australia and New Zealand	5
Africa	1
Asia	6

Table 2

Percentage of total survey respondents who reported one or more physical, mental, emotional, or spiritual benefit of yoga who experienced these benefits (n=2620)

Benefit type	Benefit	Percent of respondents
Physical	Physically flexible	87
	Healing from a pain or injury	80
	Physically stronger	77
Mental/emotional	Manage daily stress well	69
	Handle ups and downs with equanimity	68
	React with equanimity in difficult situations	51
	Feel very self-confident	47
	Easily concentrate on daily activities	47
Spiritual	Spiritual values and priorities	53
	Desire a spiritual awakening	36
	Feel connected to god	26
Relational	Feel compassionate toward others	60

Multiple logistic regression was used to identify which approaches to hatha yoga practice predicted participants reporting particular benefits. To determine which variables were to be entered as predictors into the multiple logistic regression models, Chi-square tests were used to evaluate bivariate associations between individual yoga practice approaches (e.g., frequency of practice) and the likelihood of reporting each benefit (e.g., physical strength). A backward elimination model selection procedure was used to select all final models. Odds ratios and predicted probabilities were used to report the strength of predictors in the final logistic regression models, and a value of P ≤ 0.01 was used to delineate statistical significance. All analyses were performed using R version x64 3.3.2 statistical software package.

Results

Consistent with earlier surveys,[135] our sample population was primarily female (84%), between the age group of 31 and 60 (79%), and resided in North America or Europe [86%; Table 1].

Tables detailing the practice habits of our sample population were previously published.[25] Eighty-one percent of our sample population had practiced yoga for four or more years. Survey respondents primarily reported practicing in the morning (65%), rather than afternoon (10%) or evening (25%), for a duration of 60–90 min (80%). Forty-one percent of respondents self-identified as practicing yoga “consistently,” whereas the rest (59%) reported practicing “off and on.” Survey participants reported practicing yoga either with or without a teacher between 1 and 7 days per week, with neither practicing with or without a teacher being significantly more common. The majority of survey respondents (80%) had practiced with three teachers or less in the 30 days previous to taking the survey. The majority of their teachers (79%) had practiced yoga for 7 years or more and were registered teachers (85%) with either U.S.-based Yoga Alliance or another yoga teacher organization. Sixty percent of our survey respondents were also yoga teachers themselves.

A majority of practitioners reported the physical benefits of yoga such as increased flexibility (87%) and increased physical strength [77%; Table 2]. Eighty percent of respondents also reported that yoga contributed to healing pain or injury in their body (n = 2629).

A large percentage of practitioners (47%–69%) reported at least one mental or emotional benefit of yoga practice [handling stress, equanimity, concentration, or self-confidence; Table 2]. Between 26% and 53% of respondents reported at least one spiritual benefit of yoga practice [spiritual values and priorities, desire a spiritual awakening, or feel connected to God; Table 2]. Sixty percent of respondents reported often experiencing compassion for others as a benefit of yoga practice [Table 2].

Most aspects of practice approach had a limited effect on the benefits reported by practitioners [Tables 3-5]. However, frequency of practice was a positive predictor of reporting nearly all benefits of yoga, with an increased likelihood of experiencing most benefits when the practitioner did yoga five or more days per week [Tables 3-5 and Figure 1]. Reporting self-confidence as a benefit of yoga was positively predicted by practicing 3–5 days per week without a teacher but was not related to the frequency of practice with a teacher [Table 4]. Self-reported consistency of practice, compared to off and on, was also a positive predictor for physical, mental, and emotional benefits [Tables 3 and 4], while teaching yoga was a positive predictor for physical, mental, emotional, and spiritual benefits [Tables 3-5]. Doing an evening yoga practice was a negative predictor of practitioners’ experience of concentration and equanimity in daily ups and downs when compared with morning practice, but there was no difference between doing a morning and afternoon practice [Table 4].

Table 3

Odds ratios with 95% confidence intervals in final logistic regression models predicting reporting of physical benefits of yoga participation by survey respondents (n=2605)

Predictors	Physically flexible	Physically stronger	Healing from pain or injury
Years of practice
0-3	-	-	Ref
4-10	-	-	1.03 (0.78-1.35)
>10	-	-	1.48 (1.10-2.00)*
Consistency of practice
Off and on	Ref	Ref	-
Consistently	1.78 (1.41-2.25)*	1.55 (1.28-1.87)*	-
Days practice with teacher (/week)
2 or less	-	-	Ref
3-4	-	-	1.31 (1.02-1.70)
5-7	-	-	1.48 (1.14-1.92)*
Days practice without teacher (/week)
2 or less	-	-	Ref
3-4	-	-	1.24 (0.96-1.62)
5-7	-	-	1.54 (1.17-2.03)*
Duration of practice (min)
<30	-	Ref	Ref
30	-	1.98 (0.89-4.42)	-
60	-	2.55 (1.24-5.20)*	-
90	-	3.27 (1.60-6.67)*	-
120	-	4.04 (1.87-8.72)*	-
>120	-	5.26 (2.04-14.26)*	-
Teach yoga
No	-	Ref	Ref
Yes	-	1.58 (1.31-1.91)*	1.43 (1.13-1.82)*
Authorized/certified teacher
No	-	-	Ref
Yoga alliance	-	-	1.56 (1.15-2.11)*
Other organization	-	-	1.23 (0.92-1.64)

*P≤0.01. Ref=Reference category

Table 5

Odds ratios with 95% confidence intervals in final logistic regression models predicting reporting of spiritual and relational benefits of yoga participation by survey respondents (n=2605)

Predictors	Spiritual values and priorities	Desire a spiritual awakening	Feel connected to god	Compassionate towards others
Years of practice
0-3	-	Ref	-	-
4-10	-	0.71 (0.56-0.90)*,†	-	-
>10	-	0.59 (0.46-0.75)*,†	-	-
Consistency of practice
Off and on	-	Ref	-	-
Consistently	-	0.76 (0.64-0.91)*,†	-	-
Days practice with teacher (/week)
2 or less	Ref	Ref	Ref	Ref
3-4	1.17 (0.95-1.44)	1.48 (1.19-1.83)*	1.22 (0.96-1.55)	1.26 (1.02-1.56)
5-7	1.50 (1.22-1.84)*	1.56 (1.26-1.93)*	1.38 (1.10-1.73)*	1.60 (1.29-1.99)*
Days practice without teacher (/week)
2 or less	Ref	Ref	Ref	Ref
3-4	1.53 (1.24-1.89)*	1.37 (1.11-1.70)*	1.33 (1.04-1.69)	1.20 (0.97-1.50)
5-7	1.59 (1.28-1.97)*	1.46 (1.18-1.81)*	1.61 (1.27-2.04)*	1.39 (1.12-1.75)*
Teach yoga
No	Ref	-	Ref	Ref
Yes	1.65 (1.38-1.98)*	-	2.00 (1.62-2.48)*	2.13 (1.78-2.55)*
Number of yoga teachers in the last 30 days
0-1 teachers	-	-	-	Ref
2-3	-	-	-	1.25 (1.03-1.51)
4 or more	-	-	-	1.64 (1.29-2.10)*
Number of years your yoga teacher has been practicing
<1				Ref
1-3	-	-	-	0.90 (0.52-1.57)
4-6	-	-	-	1.34 (0.88-2.04)
7-10	-	-	-	1.25 (0.88-1.78)
>10	-	-	-	*1.52 (1.18-1.97)*
Authorized/certified teacher
No	Ref	Ref	Ref	-
Yoga alliance	1.62 (1.26-2.11)*	1.70 (1.30-2.23)*	1.51 (1.10-2.05)*	-
Other organization	1.72 (1.34-2.21)*	1.58 (1.22-2.07)*	1.49 (1.09-2.05)*	-

*P≤0.01, †β estimate was negative. Ref=Reference category

Figure 1

Predicted probabilities are shown for all potential benefits of yoga that were evaluated at n days of weekly practice (2 or less, 3–4, or 5 or more) both with (a) and without (b) a teacher

Table 4

Odds ratios with 95% confidence intervals in final logistic regression models predicting reporting of mental and emotional, benefits of yoga participation by survey respondents (n=2605)

Predictors	Manage daily stress	Equanimity in daily ups and downs	Equanimity in difficult situations	Concentrate easily on daily activities	Feel very self-confident
Years of practice
0-3	-	Ref	Ref	-	-
4-10	-	1.08 (0.85-1.37)	1.19 (0.94-1.52)	-	-
>10	-	1.70 (1.32-2.20)*	1.52 (1.19-1.96)*	-	-
Consistency of practice
Off and on	Ref	-	Ref	-	Ref
Consistently	1.34 (1.12-1.61)*	-	1.35 (1.14-1.60)*	-	1.29 (1.10-1.52)*
Days practice with teacher (/week)
2 or less	Ref	Ref	Ref	Ref	-
3-4	1.35 (1.09-1.69)*	1.04 (0.85-1.28)	1.03 (0.83-1.27)	1.31 (1.07-1.62)*	-
5-7	1.49 (1.19-1.86)*	1.62 (1.30-2.03)*	1.49 (1.20-1.84)*	1.77 (1.44-2.17)*	-
Days practice without teacher (/week)
2 or less	Ref	-	Ref	Ref	Ref
3-4	1.32 (1.06-1.64)*	-	1.26 (1.02-1.56)	1.64 (1.33-2.01)*	1.25 (1.02-1.53)
5-7	1.58 (1.27-1.97)*	-	1.39 (1.12-1.73)*	1.75 (1.43-2.15)*	1.48 (1.22-1.79)*
Duration of practice (min)
<30	-	-	Ref	-	-
30	-	-	1.84 (0.68-5.58)	-	-
60	-	-	2.95 (1.19-8.38)	-	-
90	-	-	3.29 (1.33-9.34)*	-	-
120	-	-	4.16 (1.63-12.10)*	-	-
>120	-	-	5.11 (1.82-16.07)*	-	-
Time of day of yoga practice
Morning		Ref	-	Ref	Ref
Afternoon	-	1.06 (0.78-1.45)	-	0.74 (0.55-0.98)	-
Evening	-	0.75 (0.62-0.92)*,†	-	0.68 (0.56-0.82)*,†	-
Teach yoga
No		Ref	Ref		Ref
Yes	-	1.64 (1.35-1.98)*	1.50 (1.24-1.82)*	-	1.31 (1.10-1.56)*
Authorized/certified teacher
No					Ref
Yoga alliance	-	-	-	-	1.54 (1.20-1.98)*
Other organization	-	-	-	-	1.29 (1.01-1.64)

*P≤0.01, †β estimate was negative. Ref=Reference category

The experience level of the practitioner also affected some benefits [Tables 3-5]. Practicing yoga for more than 10 years was a positive predictor of equanimity in daily ups and downs, equanimity in difficult situations, and healing from physical pain or injury, but was not a positive predictor of any other benefits. On the other hand, greater years of practice experience (either 4–10 or more than 10) were a negative predictor of reporting the desire for a spiritual awakening.

The experience level of the teacher affected the relational, mental, emotional, physical, and spiritual benefits of yoga reported by practitioners. Having a teacher who had practiced for more than 10 years was a positive predictor of feeling compassion for others as a benefit of yoga [Table 5]. Having a yoga teacher who was registered with Yoga Alliance was a positive predictor of reporting self-confidence, and healing from a pain or injury [Tables 3-5], while having a yoga teacher who was registered with Yoga Alliance or authorized/certified to teach by another organization was a positive predictor of multiple spiritual benefits [Table 5].

Discussion

Our study supports the traditional text, the Hatha Yoga Pradipika,[2] and the research of others,[35] indicating that numerous benefits are experienced by yoga practitioners. Physical benefits were reported by the highest percentage, followed by mental and emotional benefits; spiritual benefits were reported by the smallest group of respondents. In the Western context characterized by our sample population, it may be that many participants are not seeking spiritual experiences from their yoga practice, but rather, as reported by others,[71214] are seeking mental and physical health and wellness. Penman et al., in 2012,[5] noted that only 19% of their yoga survey respondents began yoga as a spiritual practice, whereas Park et al., 2016,[14] reported that nearly 50% of yoga practitioners listed spirituality as a reason to continue practicing yoga, suggesting that while yoga practitioners may not initially seek spiritual benefits, this may change over time. However, the present findings showed that the likelihood of reporting a desire for a spiritual awakening decreased with a number of years of practice. Our results suggest that many practitioners remain primarily interested in nonspiritual benefits of practice even over time. On the other hand, participants may also report decreased desire for spiritual awakening over time, because they find equanimity and balance in other parts of life. Future research needs to address this question.

Frequency of weekly yoga practice was the most consistent positive predictor of experiencing benefits; only physical strength and flexibility were unrelated to frequency of practice. A greater likelihood of reporting benefits occurred when yoga participants practiced yoga for five or more days per week. Others have similarly reported that the frequency of yoga practice increased the likelihood of experiencing benefits.[4101926] Yoga practitioners who were highly involved with yoga practice experienced significantly greater mindfulness, greater spiritual well-being, and less negative states, such as depression, compared to practitioners who were marginally involved.[19] Similarly, women who practiced yoga or meditation often reported better overall health when compared with those who practiced yoga or meditation sometimes, rarely, or never.[26]

Only self-confidence was positively predicted by frequent practice without a teacher (3–5 days/week), but not by frequent practice with a teacher. It may be that practitioners who regularly practice on their own develop more self-confidence as they work through challenges of yoga practice by themselves, or vice versa that yoga practitioners who already possess more self-confidence are drawn to home practice. As with our study, Ross et al in 2012,[10] found that frequency of home yoga practice was a positive predictor of a number of benefits including mindfulness, well-being, body mass index, and level of fatigue. Frequency of home practice was a predictor of benefits more often than years of practice, gender, or age.[10] As the number of days of home practice per month increased, amount of many health benefits increased as well (e.g., increased consumption of fruit and vegetables and mindfulness scores).[10]

Our study supports the Hatha Yoga Pradipika,[2] in that, morning yoga practice may be preferable for experiencing some benefits. While the time of day of yoga practice had no effect on practitioners’ experience of many benefits, practicing in the evening was a negative predictor of both concentration and equanimity in daily ups and downs when compared to doing a morning yoga practice. Those doing yoga practice in the evening may feel more distracted or bothered by the thoughts and events of the day than those doing their yoga practice in the morning before they begin their daily activities.

We were surprised that most benefits were just as likely to be reported by practitioners in their first 3 years of practice as they were by more experienced practitioners (4–10 years, or more than 10 years practice). A greater number of years of practice was only a positive predictor of healing from pain or injury with yoga, equanimity during ups and downs, and equanimity in difficult situations [Tables 3 and 4]. Others also found that yoga practitioners reported benefits within weeks of beginning practice.[924] However, as the number of years of yoga practice increased, Park et al., 2016[14] found that yoga practitioners gave more emphasis to the mental, emotional, and spiritual benefits compared to physical benefits. Similarly, Ross et al., in 2012,[10] reported that total years of practice was a positive predictor of experiencing mindfulness as a benefit of yoga. It is possible that many benefits of yoga are accessible to beginning practitioners, but that the benefits which practitioners are most aware of shift as they become more experienced.

We found little relationship between the benefits of yoga reported by students and the number of years that their teacher had been practicing yoga. However, we did find that having a teacher who was authorized/certified by Yoga Alliance or another organization was a positive predictor of experiencing benefits of a spiritual nature. It is possible that teachers who made the additional effort to achieve authorization/certification are also more interested in the broader aspects of yoga, including spirituality, and are therefore more likely to communicate these ideas to their students. While the notation of a certified, authorized, registered, or other teacher designation suggests a greater commitment on the part of the teacher, this is still problematic as a sole measure of teacher experience because there is no existing national or international certifying board that issues licenses for yoga instructors.

Teaching yoga, itself, was a positive predictor of physical, mental, emotional, spiritual, and relational benefits of yoga [Tables 3-5], even when the frequency of practice and years of practice were accounted for. Teachers may have gone further in integrating the practice and be using it for more subtle work, such as self-actualization. Teachers may have sought out yoga as a vocation because of their depth of interest in the practices and may be more focused on, the broader potential effects beyond physical wellness.

Limitations

Limitations exist in the interpretation of findings from our study. We collected self-reported survey data, and we acknowledge potential bias in the self-selective nature of the sample. While the sociodemographics of our sample population were similar to those of other published studies of English-speaking yoga practitioners, these characteristics, including the large percentage of yoga teachers in our sample, may themselves be associated with benefits that one might experience from yoga asana practice. In addition, as survey completion was limited to those who were proficient with the English language, this may have limited the breadth of responses that we received. Finally, survey completion was online, which required that participants have computer and Internet access.

Conclusions

Frequency of weekly yoga practice was a consistent positive predictor of physical, mental, emotional, spiritual, and relational benefits of yoga practice, particularly when practice frequency increased to five or more days per week. The potential for experiencing benefits from yoga may be greater than previously published, provided that practitioners increase practice frequency. Most other approaches to yoga practice, however, had little if any relationship to likelihood of experiencing particular types of benefits. The limited relationship between benefits and many approaches to yoga practice, such as practice duration and time of day, suggests that practitioners can choose the approaches that work best for them and still have a similar likelihood of experiencing physical, mental, emotional, spiritual, and relational benefits.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.